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arises from the antero-dorsal region of the ganglion, 
passes upwards, and fuses with the R. spinosus of the 
nerve in front (third spinal). 
2. R. spinosus (7. sp. 4).—A motor ramus leaving 
the postero-dorsal region of the ganglion, and giving off 
near its base a posterior lateral branch for the inter- 
mediate portion of the dorsal musculature. It then 
passes dorsally, and fuses with the R. communicans of the 
nerve behind (fifth spinal). The resulting mixed trunk 
continues upwards and forwards in the dorsal musculature 
very close to the middle line, and is distributed to the 
dorsal portion of the dorsal musculature, the inter-spinal 
muscles and the dorsal skin. 
3. R. medius (7. m. 4)—This mixed ramus, leaving 
the ventral extremity of the ganglion, courses laterally 
outwards through the ventral portion of the dorsal museu- - 
lature, and bifurcates. The upper division accompanies 
the intermuscular bone, and supphes the ventral portion 
of the dorsal musculature. The lower division passes 
downwards into the lateral musculature (which it sup- 
plies), obliquely crossing under the R. lateralis profundus 
vagi (fig. 23, r. lat. prof. «#.), to which it may be very 
closely attached, but with which it never mingles. The 
sensory fibres of the ramus pass out laterally to the skin, 
and supply that portion of it around the lateral sensory 
canal. 
4. R. ventralis (7. v. 4)—This mixed ramus also 
arises from the ventral extremity of the ganglion, and is 
the largest of all. It passes downwards, and just over the 
kidney receives the R. communicans from the fourth 
spinal sympathetic ganglion (com. zv.). It then turns out- 
wards between the lateral musculature and the kidney, 
and afterwards downwards again between the lateral 
musculature and the liver. Finally it continues down- 
